Remove foldable from ScreenLine

spec/app/display-buffer-spec.coffee

@@ -145,21 +145,6 @@ describe "DisplayBuffer", ->
         expect(event.lineNumbersChanged).toBeTruthy()
 
   describe "structural folding", ->
-    describe "the foldable flag on screen lines", ->
-      it "sets 'foldable' to true for screen lines that start a foldable region", ->
-        expect(displayBuffer.lineForRow(0).foldable).toBeTruthy()
-        expect(displayBuffer.lineForRow(1).foldable).toBeTruthy()
-        expect(displayBuffer.lineForRow(2).foldable).toBeFalsy()
-        expect(displayBuffer.lineForRow(3).foldable).toBeFalsy()
-
-      describe "when a foldable line is wrapped", ->
-        it "only marks the first screen line as foldable", ->
-          displayBuffer.setSoftWrapColumn(20)
-          expect(displayBuffer.lineForRow(0).foldable).toBeTruthy()
-          expect(displayBuffer.lineForRow(1).foldable).toBeFalsy()
-          expect(displayBuffer.lineForRow(2).foldable).toBeTruthy()
-          expect(displayBuffer.lineForRow(3).foldable).toBeFalsy()
-
     describe ".unfoldAll()", ->
       it "unfolds every folded line", ->
         displayBuffer.foldBufferRow(0)

src/app/display-buffer.coffee

@@ -222,7 +222,6 @@ class DisplayBuffer
     startBufferColumn = 0
     while currentBufferRow <= endBufferRow
       screenLine = @tokenizedBuffer.lineForScreenRow(currentBufferRow)
-      screenLine.foldable = @languageMode.doesBufferRowStartFold(currentBufferRow)
 
       if fold = @largestFoldStartingAtBufferRow(currentBufferRow)
         screenLine = screenLine.copy()

src/app/screen-line.coffee

@@ -2,14 +2,13 @@ _ = require 'underscore'
 
 module.exports =
 class ScreenLine
-  constructor: ({@tokens, @ruleStack, @bufferRows, @startBufferColumn, @fold, @foldable}) ->
+  constructor: ({@tokens, @ruleStack, @bufferRows, @startBufferColumn, @fold}) ->
     @bufferRows ?= 1
     @startBufferColumn ?= 0
-    @foldable ?= false
     @text = _.pluck(@tokens, 'value').join('')
 
   copy: ->
-    new ScreenLine({@tokens, @ruleStack, @bufferRows, @startBufferColumn, @fold, @foldable})
+    new ScreenLine({@tokens, @ruleStack, @bufferRows, @startBufferColumn, @fold})
 
   clipScreenColumn: (column, options={}) ->
     { skipAtomicTokens } = options
@@ -74,7 +73,6 @@ class ScreenLine
       bufferRows: 0
       startBufferColumn: @startBufferColumn
       ruleStack: @ruleStack
-      foldable: @foldable
     )
     rightFragment = new ScreenLine(
       tokens: rightTokens